JP7099757B1 - Semiconductor wafer polishing equipment - Google Patents

Abstract

An object of the present invention is to maintain the polishing accuracy of the outer peripheral portion of a semiconductor wafer at high accuracy over a long period of time. A polishing apparatus (10) includes a column (17) provided with a chuck (21) for holding a semiconductor wafer (W), a reciprocating table (14) mounted on a base member (13) so as to freely reciprocate, and a polishing apparatus (10) which rotatably supports a polishing pad (66). A pressing force imparting member having a head 55 and a support table 48 supporting a slide plate 54 to which the polishing head 55 is attached, and applying a pressing force toward the polishing head 55 to the semiconductor wafer via the reciprocating table 14. A cylinder 41 is mounted on the base member 13, and a load cell 76 of an actual load measuring device for measuring the actual load applied to the semiconductor wafer by the pressing force imparting member is mounted between the support table and the slide plate. [Selection drawing] Fig. 2

Description

The present invention relates to a wafer polishing apparatus that polishes the outer peripheral portion of a semiconductor wafer.

As a semiconductor wafer used as a material for a semiconductor integrated circuit, a single crystal of silicon is generally used, and this is called a silicon wafer. A silicon wafer is manufactured by thinly slicing an ingot made by processing a raw material into a columnar shape, and a large number of circuit patterns such as wiring and elements of a semiconductor integrated circuit are formed on the surface. A silicon wafer on which a large number of circuit patterns are formed is cut into a single semiconductor chip by dicing.

A V-shaped notch called an orientation notch or a straight line portion called an orientation flat is ground on the outer peripheral portion of the semiconductor wafer in order to indicate the crystal orientation. In the process of forming a circuit pattern on a semiconductor wafer, the orientation of the wafer is aligned by a notch or a flat.

Orientation notches and flats machined on the outer peripheral portion of the semiconductor wafer are polished by a polishing device. The semiconductor wafer is held by a chuck during polishing, and Patent Document 1 describes a chuck for holding the semiconductor wafer. The chuck is mounted on the reciprocating table, the reciprocating table is reciprocally arranged on the base member, and the disk-shaped polishing pad for polishing the outer peripheral portion of the semiconductor wafer is rotatably attached to the support table. .. The semiconductor wafer held by the chuck is pressed against the polishing pad by the reciprocating table.

Japanese Unexamined Patent Publication No. 2006-116643

In order to apply the load required for polishing from the polishing pad to the outer peripheral portion of the semiconductor wafer, a pressing cylinder made of a pneumatic cylinder is attached to the reciprocating table. In order to measure the pressing force applied to the semiconductor wafer from the polishing pad during the polishing process, an attempt is made to mount a load cell between the rod of the pressing cylinder and the reciprocating table.

The reciprocating table provided with the chuck is movably mounted on the base member, and sliding resistance is applied to the reciprocating table with respect to the base member. Further, a plurality of wires and pipes are connected to the chuck, and the resistance of the wires and pipes is added to the slide table. If these resistances change over time or over time, it is possible that the actual polishing load applied from the polishing pad to the semiconductor wafer becomes unstable.

As described above, if a load cell is provided in the pressing cylinder in order to detect the pressing force applied to the semiconductor wafer from the polishing pad, does the load cell output the pressing load on the reciprocating table by the extrusion cylinder according to the command value? It will be monitored whether or not. Therefore, if the sliding resistance applied to the reciprocating table changes over time or changes over time, the actual load itself applied to the semiconductor wafer from the polishing pad cannot be accurately monitored by the load cell. If an error in the actual load with respect to the set value of the pressing force occurs, the accuracy of the polishing process of the notch on the outer peripheral portion of the semiconductor wafer and the orientation flat will decrease.

An object of the present invention is to enable the polishing process accuracy of the outer peripheral portion of a semiconductor wafer to be maintained with high accuracy for a long period of time.

The semiconductor wafer polishing apparatus of the present invention has a column provided with a chuck for holding the semiconductor wafer, a reciprocating table that is reciprocally mounted on a base member and to which the column is mounted, and a reciprocating direction of the reciprocating table. The reciprocating table moves a polishing head that rotatably supports a polishing pad that has a rotation center axis perpendicular to the direction of rotation and polishes the outer peripheral portion of the semiconductor wafer, and a slide plate to which the polishing head is attached. A support table that is movably supported in the same direction as the direction, a pressing force applying member that is mounted on the base member and applies a pressing force toward the polishing head to the semiconductor wafer via the reciprocating table, and the support. It has an actual load measuring device which is attached to one of the table and the slide plate and measures the actual load applied to the polishing pad and the semiconductor wafer by the pressing force applying member.

Since the actual load, which is the pressing force applied from the polishing pad to the outer peripheral portion of the semiconductor wafer, can be set with high accuracy, the polishing processing accuracy of the outer peripheral portion of the semiconductor wafer can be maintained for a long period of time.

It is a perspective view which shows the polishing apparatus of a semiconductor wafer. It is a front view of FIG. It is a right side view of FIG. It is a top view which shows the semiconductor wafer which the notch for orientation was machined. It is a top view which shows the semiconductor wafer which processed the flat for orientation. It is an enlarged perspective view of the chuck drive unit shown in FIG. 1. It is a front view of FIG. It is an enlarged front view which shows the pad drive unit in FIG. 1. It is a perspective view which shows the back side of FIG. 7. It is a perspective view which shows the upper part of FIG. 7. It is a pneumatic circuit for supplying compressed air to the pressing cylinder. It is a block diagram which shows the control circuit of a polishing apparatus. It is a schematic diagram which shows the measuring principle of the pressing force of the polishing pad of this invention. It is the schematic which shows the measuring principle of the pressing force of a polishing pad as a comparative example.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The semiconductor wafer polishing apparatus 10 shown in FIGS. 1 to 3 shows a state in which an orientation notch machined in advance on the outer peripheral portion of the semiconductor wafer W is polished. The polishing device 10 can polish not only the notch but also the flat for orientation. FIG. 4a shows a work, that is, a semiconductor wafer W in which an orientation notch V is machined on the outer peripheral portion, and FIG. 4b shows a semiconductor wafer W in which a flat F is machined.

As shown in FIGS. 1 to 3, the polishing apparatus 10 includes a chuck drive unit 11 that drives a chuck that holds a semiconductor wafer W that is a work, and a notch V or a flat F that is pre-processed on the outer peripheral portion of the work W. It is provided with a pad drive unit 12 for driving a polishing pad for polishing.

(Chuck drive unit)
As shown in FIGS. 5 and 6, the chuck drive unit 11 includes a reciprocating table 14 that is reciprocally mounted in a linear direction on a base member 13 installed in the horizontal direction. A guide block 15 is attached to the reciprocating table 14, the guide block 15 is movably mounted along a guide rail 16 fixed to the base member 13, and the reciprocating table 14 is guided by the guide rail 16. Moving. The moving direction of the reciprocating table 14 is the X-axis direction shown in FIGS. 1 and 6, and when the surface of the chuck drive unit 11 shown in FIG. 6 is the front surface, the moving direction of the reciprocating table 14 is the left-right direction. .. Note that the base member 13 is not shown in FIGS. 1 and 5.

A column 17 is attached to the reciprocating table 14, a swing shaft 18 is rotatably provided on the column 17, and a tip portion of the swing shaft 18 projects from the front surface of the column 17. The swing shaft 18 has a swing center axis O extending in the Y-axis direction perpendicular to the X-axis direction, and the swing shaft 18 is provided with a swing arm 19. The swing arm 19 is provided with a chuck 21 for holding the semiconductor wafer W. As shown in FIGS. 5 and 6, the chuck 21 can swing around the swing shaft 18 in a range of an angle θ in the vertical direction, and in the case of drawing, the chuck 21 can swing up and down with respect to the horizontal position, respectively. It swings in the range of 70 °.

The chuck 21 has a drive case 22 attached to the swing arm 19, and a holding member 23 is provided on one side of the drive case 22, and a movable holding member 24 is provided on the other side. Each of the holding members 23 includes two holding rods 25 extending in the X-axis direction, and two claw portions 25a in contact with the outer peripheral surface of the work W are provided at the tip of each holding rod 25. As shown in FIG. 5, a space 26 for polishing is formed between the two claw portions 25a. On the other hand, the holding member 24 extends in a direction perpendicular to the holding rod 25, and two claw portions 24a in contact with the outer peripheral surface of the work W are provided at both ends. The distance between the two claw portions 24a is wider than that of the space 26. The claw portions 25a and 24a are formed of a material having appropriate elasticity and chemical resistance, such as fluororubber.

An air cylinder (not shown) is incorporated inside the drive case 22, and the holding member 24 is attached to a rod 27 of the air cylinder. The claw portion 24a of the holding member 24 can reciprocate in a direction of approaching and separating from the claw portion 25a of the holding member 23 by an air cylinder, and the claw portions 25a and 24a come into contact with the outer periphery of the work W. The work W is supported by the chuck 21. A support surface for supporting the work W is formed by the four claw portions 25a and 24a, and the support surface swings in a range of an angle θ around the swing center axis O. The swing center portion of the support surface, that is, the swing center portion of the work W is the position of the swing center axis O in the space 26 between the two claw portions 25a.

A pipe 28 made of a hose or the like for supplying / discharging compressed air to / from an internal air cylinder is attached to the drive case 22 as shown in FIG. A wiring 29 made of a signal cable or the like for sending a control signal for controlling the driving of the air cylinder is further attached to the drive case 22. The pipe 28 and the wiring 29 are connected to an external control device, and wiring and piping (not shown) are provided between the control device and the column 17.

A drive box 31 is fixed to the lower surface of the column 17, and the drive box 31 projects below the base member 13 from a through hole 32 formed in the base member 13. An electric motor 33 for swinging the work is attached to the front surface of the drive box 31, and a pulley 34 provided on the main shaft of the electric motor 33 is provided in the drive box 31 and a pulley provided on the swing shaft 18. A 35 is provided in the column 17, and a belt 36 is hung between both pulleys 34 and 35. The rotation of the spindle of the electric motor 33 is transmitted to the chuck 21 via the belt 36, and the work W is driven by the electric motor 33 around the center of the swing.

(Drive of column)
As shown in FIG. 6, a guide rail 37 extends in the X-axis direction and is attached to the lower surface of the base member 13, and an electric motor 38 for positioning is attached to the guide rail 37. The slide block 39 mounted on the guide rail 37 is screw-coupled to a ball screw that is rotationally driven by the spindle of the electric motor 38, and the slide block 39 is reciprocated in the X-axis direction by the electric motor 38.

The push cylinder 41 made of a pneumatic cylinder is attached to the slide block 39 via the bracket 42, and the piston rod 43 of the push cylinder 41 penetrates the mounting base 67 fixed to the drive box 31 and is pressed against the connecting block 44. There is. As a result, when the piston rod 43 of the pressing cylinder 41 is driven in the protruding direction, the column 17 is driven to the left in FIG. The piston rod 43 is provided with a contact member 43a made of a nut or the like that comes into contact with the inner surface of the mounting base 67. When the piston rod 43 moves backward, the contact member 43a comes into contact with the mounting base 67 to form a column. 17 is driven to the right in FIG. In this way, the chuck 21 is reciprocated by the electric motor 38 between the machining position shown in FIGS. 2 and 6 and the work mounting position in the right direction in FIG. 6 from this position.

(Pad drive unit)
The pad drive unit 12 includes a support base 45 as shown in FIG. As shown in FIGS. 7 to 9, two guide rails 46 are attached to the support base 45 extending in the Y-axis direction, and are supported by the slide block 47 mounted on each guide rail 46. A table 48 is attached. A pedestal 49 is attached to the pedestal 45, an electric motor 51 for oscillation is attached to the pedestal 49, and a feed screw 52 attached to the spindle of the electric motor 51 is a nut assembly fixed to the support table 48. It is screwed to the nut of 53. Therefore, the support table 48 is moved in the Y-axis direction by the electric motor 51. In addition, in FIG. 1, FIG. 8 and FIG. 9, the support base 45 is not shown.

The slide plate 54 is movably mounted on the support table 48 in the X-axis direction, which is the same direction as the reciprocating table 14, and the polishing head 55 is mounted on the lower surface of the slide plate 54 in the vertical direction, that is, in the Z-axis direction. Has been done. The polishing head 55 is formed of a hollow pillar-shaped case member, penetrates through the through hole 56 formed in the support table 48 and the through hole 57 formed in the support base 45, and is below the support base 45. It stands out. A pulley 61 on the drive side is rotatably mounted on the front side of the support plate 58 vertically fixed to the upper surface of the slide plate 54. A polishing shaft 62 is rotatably mounted on the lower end of the polishing head 55, and a driven pulley 63 attached to the polishing shaft 62 is arranged in the polishing head 55 and protrudes to the back surface side of the polishing head 55. A belt 64 is hung between both pulleys 61 and 63. As shown in FIGS. 8 and 9, an electric motor 65 for polishing is mounted on the back surface side of the support plate 58, and the pulley 61 on the drive side is attached to the main shaft of the electric motor 65. The feeder line that supplies electric power to the electric motor 65 is connected to a control device fixed to the outside.

(Polishing pad)
Two disc-shaped polishing pads 66 are mounted on the polishing shaft 62, and the polishing pads 66 are rotationally driven by an electric motor 65 via a belt 64. The rotation center axis P of the polishing pad 66 is in the Y-axis direction, is a direction perpendicular to the X-axis direction which is the reciprocating movement direction of the reciprocating table 14, and the rotation center axis P is a direction parallel to the support table 48. .. The polished surface of the outer peripheral portion of the polishing pad 66 that rotates about the rotation center axis P rotates and moves in a direction crossing the outer peripheral portion of the work W, and the outer peripheral portion of the work W is polished. Since the polishing head 55 is provided with a plurality of polishing pads 66, the notch V can be polished by any of the polishing pads 66. When one polishing pad 66 is worn, the notch V of the new work W can be machined by the other polishing pad 66. As a result, the time required to replace the polishing pad 66 with a new polishing pad 66 can be extended.

(Pressing force of polishing pad)
When the outer peripheral portion of the semiconductor wafer W is polished by the polishing pad 66, a pressing force is applied to the work W via the connecting block 44, the drive box 31, the column 17 and the chuck 21 by the pressing cylinder 41 toward the polishing pad 66. Be done. When a pressing force is applied from the semiconductor wafer W to the polishing pad 66, a pressing force is applied from the polishing pad 66 to the outer peripheral portion of the semiconductor wafer W as a reaction force. As described above, the pressing cylinder 41 constitutes a pressing force applying member that applies a pressing force toward the polishing pad 66 to the semiconductor wafer W. The pressing force applying member is not limited to the pressing cylinder 41, and the pressing force may be applied via the connecting block 44 by an electric motor for driving the feed screw, a compression coil spring, or the like.

As shown in FIG. 6, the mounting base 67 fixed to the drive box 31 is provided with a pushing amount measuring device 68 for detecting the pushing stroke of the pushing cylinder 41. When the slide block 39 is driven to the left in FIG. 2 by the electric motor 38, the drive box 31 is driven to the left by the pressing cylinder 41 via the mounting base 67 as described above.

FIG. 10 is an pneumatic circuit for supplying compressed air to the pressing cylinder 41, and the compressed air discharged from the pneumatic supply source 71 is connected to the pipe 72 connecting the pneumatic supply source 71 made of a compressor or the like and the pressing cylinder 41. A pressure adjusting valve 73 for adjusting the pressure of the above, and an on-off valve 74 for switching between a state of supplying compressed air to the pressing cylinder 41 and a state of shutting off the supply are provided. In this way, the pressing force set by the pressure adjusting valve 73 and applied to the outer peripheral surface of the semiconductor wafer W by the compressed air of the pressure supplied to the pressurizing chamber of the pressing cylinder 41 is set.

(Measurement of actual load of pressing force)
As shown in FIGS. 7 to 9, the bracket 75 is fixed to the support table 48, and the load cell 76 is attached to the bracket 75 as an actual load measuring instrument. On the other hand, a pressure rod 78 is attached to the bracket 77 attached to the slide plate 54, and when a pressing force is applied to the polishing pad 66, the pressing force is transmitted to the load cell 76 via the pressure rod 78. , The pressing force is detected by the load cell 76. As described above, the load cell 76 is attached to the support table 48 by the bracket 75, and the pressure rod 78 is attached to the slide plate 54 by the bracket 77, but the load cell 76 is between the support table 48 and the slide plate 54. The load cell 76 may be attached to the slide plate 54 and the pressure rod 78 may be attached to the support table 48. In other words, the load cell 76 is attached to one of the support table 48 and the slide plate 54.

On the side surface of the column 17, supply pipes 79a and 79b for applying a slurry-like polishing liquid to the work and the polishing pad 66 are attached, and the supply pipe 79a is coated with the polishing liquid from the upper side of the semiconductor wafer W. , The supply pipe 79b is coated with the polishing liquid from the lower side. The application port nozzles of both supply pipes 79a and 79b face the space 26 and face each other. The respective supply pipes 79a and 79b are connected to an external polishing liquid supply unit by a pipe (not shown).

FIG. 11 is a block diagram showing a control circuit of the polishing apparatus 10, and the control unit 81 has a control program, an arithmetic expression, a memory for temporarily storing map data and data, and a microprocessor for calculating a control signal. It sends a control signal to the above-mentioned electric motors 33, 38, 51, 65. The operation panel 82 is connected to the control unit 81, and an operation switch or the like for instructing the start of the polishing work of the polishing device 10 is provided on the operation panel 82. A control signal is sent from the control unit 81 to the on-off valve 74, and when the on-off valve 74 is turned on, compressed air is supplied to the pressing cylinder 41. The pressing force applied to the polishing pad 66 by the pressing cylinder 41 is measured by the load cell 76, and the measurement signal is sent to the control unit 81.

(Notch polishing procedure)
The semiconductor wafer W having the notch V processed in advance on the outer peripheral portion is mounted on the chuck 21 and held. The work mounting position at that time is to the right of the position shown in FIG. 2, and the semiconductor wafer W is positioned and chucked so that the notch V is the center of the space 26 between the two holding rods 25. It is mounted on 21. On the other hand, the support table 48 is driven by the electric motor 51, and one of the two polishing pads 66 is positioned at the position of the space 26. Under this state, the electric motor 38 is driven, the column 17 is conveyed to the polishing position shown in FIGS. 2 and 6, the notch V is positioned at the position of the swing center axis O, and the space is formed. Positioned at position 26.

When the electric motor 38 is driven, the column 17 is driven toward the polishing head 55. When the column 17 is driven to the position where the polishing pad 66 enters the notch V, the electric motor 38 is stopped. Next, the on-off valve 74 is turned on, and the pressing force is applied to the polishing pad 66 by the pressing cylinder 41 via the column 17 and the chuck 21. The time during which the on-off valve 74 continues to be on is set by a timer provided in the control unit 81. The pressing force is detected by the load cell 76, and it is confirmed whether or not a predetermined pressing force is applied.

Under this state, the electric motor 65 is driven, the polishing pad 66 is rotationally driven, and the notch V is polished. During this polishing process, the electric motor 33 is driven, and the swing arm 19 causes the semiconductor wafer W to have an angle θ in the vertical direction as shown by an arrow from the horizontal position shown in FIG. 6 centering on the notch V portion. Swing in range. Further, the electric motor 51 is driven, and the polishing pad 66 is slightly reciprocated in the Y-axis direction to be oscillated.

(Comparison of pressing force measurement principle)
FIG. 12a is a schematic view showing the measurement principle of the pressing force of the polishing pad of the present invention, and FIG. 12b is a schematic view showing the measuring principle of the pressing force of the polishing pad as a comparative example.

As shown in FIGS. 12a and 12b, the reciprocating table 14 reciprocally mounted on the base member 13 receives the sliding resistance R1 from the base member 13 and is between the column 17 and the external fixed portion. The column 17 receives the wiring / piping resistance R2 from the mounted wiring / piping, the piping connected to the supply pipes 79a and 79b, and the like. From the pressing cylinder 41, a pressing force for sliding the reciprocating table 14 including the column 17 and the chuck 21 is applied to the reciprocating table 14. The sliding resistance R1 and the wiring / piping resistance R2 cannot avoid aging and aging.

As in the comparative example shown in FIG. 12b, the load cell 76 is mounted between the pressing cylinder 41 and the reciprocating table 14, and the pressing applied to the semiconductor wafer W by the pressing load applied to the reciprocating table 14 by the pressing cylinder 41. When the force is measured, the pressing force including the sliding resistance R1 and the wiring / piping resistance R2 is measured as the measured value. Therefore, the load cell 76 can only monitor whether the pressing load of the pressing cylinder 41 is output according to the command value, and the measured value of the load cell 76 is affected by aging and aging, so that it is added to the semiconductor wafer W. It is not the actual pressing load that is applied.

On the other hand, when the load cell 76 is arranged between the polishing head 55 and the support table 48 as in the present invention shown in FIG. 12a, the load cell 76 has a change even if the sliding resistance R1 and the wiring / piping resistance R2 change. The load actually applied to the semiconductor wafer W from the polishing pad 66 can be detected. As a result, the detection accuracy of the pressing load is improved, and the polishing quality of the outer peripheral surface of the semiconductor wafer W can be improved over a long period of time. When the slide plate 54 is moved over a long distance on the support table 48, the slide plate 54 receives the sliding resistance against the support table 48 and the piping resistance of the power feeding cable connected to the electric motor 65, but the load cell 76 detects the load. When doing so, the slide plate 54 moves only by transmitting the pressing load to the load cell 76, that is, it moves only at a distance of, for example, 1 mm or less in micron units, and the load measurement value of the load cell 76 is the sliding resistance of the slide plate 54 or the like. It does not receive the resistance of the power supply cable.

Further, the pressure of the compressed air supplied to the pressing cylinder 41 can be feedback-controlled so as to change the pressing load of the pressing cylinder 41 on the semiconductor wafer W based on the pressing load detected by the load cell 76. Since this pressure can be automatically controlled by controlling the pressure adjusting valve 73 shown in FIG. 10, the load cell 76 is supplied to the pressing cylinder 41 so as to detect the set pressing force. By controlling the pressure of the compressed air, the pressing force of the polishing pad 66 can always be maintained at the set value.

(Polishing of orientation flat)
As shown in FIG. 4b, the polishing apparatus 10 can also perform polishing processing of the flat F of the semiconductor wafer W. At that time, instead of the polishing pad 66 on the disk, a cylindrical polishing pad is attached to the polishing head 55. Further, the holding rod 25 shown in FIG. 5 is replaced for flat polishing. The size of the space 26 of the holding rod 25 for flat polishing is different from that for notch polishing.

The present invention is not limited to the above embodiment, and various modifications can be made without departing from the gist thereof.

10 Polishing device 11 Chuck drive unit 12 Pad drive unit 13 Base member 14 Reciprocating table 17 Column 19 Swing arm 21 Chuck 26 Space 31 Drive box 41 Pushing cylinder (pressing force applying member)
45 Support stand 48 Support table 54 Slide plate 55 Polishing head 66 Polishing pad 68 Push-in amount measuring instrument,
76 Load cell (actual load measuring instrument)

Claims (4)

A column provided with a chuck for holding a semiconductor wafer,
A reciprocating table that is reciprocally mounted on the base member and to which the column is attached,
A polishing head that rotatably supports a polishing pad having a rotation center axis perpendicular to the reciprocating direction of the reciprocating table and polishing the outer peripheral portion of the semiconductor wafer.
A support table that movably supports the slide plate to which the polishing head is attached in the same direction as the moving table of the reciprocating table.
A pressing force applying member mounted on the base member and applying a pressing force toward the polishing head to the semiconductor wafer via the reciprocating table.
An actual load measuring device attached to one of the support table and the slide plate and measuring the actual load applied to the polishing pad and the semiconductor wafer by the pressing force applying member.
A semiconductor wafer polishing device with. In the semiconductor wafer polishing apparatus according to claim 1,
The column is provided with a swing arm having an outer peripheral portion of the semiconductor wafer as a swing center, and the chuck is provided on the swing arm.
A semiconductor wafer polishing device that swings around the outer peripheral portion of the semiconductor wafer to be polished by a swing arm. In the semiconductor wafer polishing apparatus according to claim 1 or 2.
A support base that movably supports the support table in a direction parallel to the rotation center axis, and
It has a feed motor provided on the support base and for driving a feed screw screw-coupled to the support table.
The polishing head has a plurality of polishing pads of the same rotation center axis, and the polishing head has a plurality of polishing pads.
A semiconductor wafer polishing device that positions one of a plurality of polishing pads at a polishing position of the semiconductor wafer by the feed motor. The semiconductor wafer polishing apparatus according to any one of claims 1 to 3.
The pressing force applying member is attached to a bracket driven by a positioning electric motor, and the positioning electric motor reciprocates the chuck between a machining position and a work mounting position via the pressing force applying member. A moving semiconductor wafer polishing device.

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